Maybe a stupid question, but what conditions warrant high or low? When would you use which and why?

ESP

09-09-2010 11:16 PM

Not a stupid question at all. Its very important to understand when each should be used and for how long. There are a million threads on the forums here about this, take a moment to search for some and then read up. If you have a specific question about using yours on your Jeep, we might be able to help more directly. :)

dfwislander

09-09-2010 11:36 PM

Thanks, I just suck at searching obviously. I didn't post without trying, I searched 4h vs 4l, high vs low, etc, and not one result dealt with this issue. I've tried just browsing and can't find a single thing. I know it's annoying repeating oneself so I won't push. I'll go try google instead. Thanks anyway.

When I am off road, I am generally in 4 high until something comes up. I change to 4 low and after the obstacle, I go back to 4 high.

thaduke2003

09-10-2010 08:03 AM

^ Largely disagreed.

4WD should only be used in low-traction conditions. Plowed roads and general trails do not require 4WD, and can cause binding when turning, which will cause driveline damage.
4 Lo should NOT be used for towing, unless you mean pulling something to the side on a trail? You should tow in 2WD, every time.

Some people tend to overuse 4Lo on the trails. You really should stick to 2Hi whenever possible to minimize wear and tear on your driveline (axles, driveshafts, axle shafts, etc.) and fuel consumption. If you don't NEED 4WD traction, don't use it.
That said, if you're going into an area where you know you'll need more grip (muddy trail, big rocks), go in in 4Hi. If that's not cutting it, stop, and shift into 4Lo. This does NOT apply to sand- get into 4Lo and stay there! (or prepare to dig out! :))- Mark W.

ESP

09-10-2010 08:38 AM

Quote:

Originally Posted by thaduke2003
(Post 765908)

^ Largely disagreed.

4WD should only be used in low-traction conditions. Plowed roads and general trails do not require 4WD, and can cause binding when turning, which will cause driveline damage.
4 Lo should NOT be used for towing, unless you mean pulling something to the side on a trail? You should tow in 2WD, every time.

Some people tend to overuse 4Lo on the trails. You really should stick to 2Hi whenever possible to minimize wear and tear on your driveline (axles, driveshafts, axle shafts, etc.) and fuel consumption. If you don't NEED 4WD traction, don't use it.
That said, if you're going into an area where you know you'll need more grip (muddy trail, big rocks), go in in 4Hi. If that's not cutting it, stop, and shift into 4Lo. This does NOT apply to sand- get into 4Lo and stay there! (or prepare to dig out! :))- Mark W.

^ Yep.

Boosta

09-10-2010 08:40 AM

Does anyone shift gears in sand in 4 lo or do you keep it in one gear?

Baileys Daddy

09-10-2010 08:41 AM

I have to agree with Thaduke. I have always driven in 2wd until 4hi was needed and then when all else fails switch to 4lo.....But this is just me and I only have experience in deep ocean sand and snow......
BD

Baileys Daddy

09-10-2010 08:45 AM

For me it depends on the conditions, but normally just keep it in 1st and keep the momentum up. You really shouldn't go faster than 15-20mph any way.........

JIMBOX

09-10-2010 09:58 AM

:cool: All specifics on 4hi/4lo use change with the JK automatic-vs-stick

If you have an auto post that you do, if you have a stick, you'll get a lot of ideas

I can help with the auto only !!

:rofl::rofl: JIMBO

Aaronkushner

09-10-2010 10:11 AM

I only shift into 4hi when I get stuck in 2wd. Other than that I am always in 2wd on the trails. Once my back wheels begin to spin and dig and mometum cannot carry me through only then I shift to 4hi.

Croakus

09-10-2010 11:17 AM

If you can get to that article, I think it's a great overview.

The problem is, a lot of what you're going to get is opinion. Including this ;-) ... but in my 20 some years of experience, 4wd is fine on almost everything except pavement. Even then, it's reasonable to engage on slippery roads like snow and ice.

Personally, you won't find me driving on gravel without 4wd ... but that's a long story for another thread ;)

As far as damage goes ... I've never heard anyone say they did damage by driving in 4wd when they shouldn't have. If anyone here has a story I'd be really interested in hearing it. The only problem I've actually seen is binding / tires slipping when the gears got out of synch ... and while that can't be good, I've never actually seen anything break. If I were to guess, I'd say you'd probably blow a $50 U-Joint before anything else.

Jeeps are tough vehicles and have one of the most time proven 4wd designs on the planet. IMO you'd have a hard time breaking it just by using it now and then. Just be reasonable with it and you should be OK.

JIMBOX

09-10-2010 11:26 AM

:cool: Thats all true and for the reason I mentioned 4hi/4lo using the auto is part of it, but

Either 4hi or 4lo selecting in the JK jeep--should be done EARLY, before the actual need occurs, while the jeep is moving, of course I mean when you near a 4wd terrain, because shifting the JK transfer case is a very particular excersize and does require some care !!

:rofl::rofl: JIMBO

NHrubicon

09-10-2010 11:46 AM

in all the trail riding I have done in NH/VT, jeep jamboree (Killington) and club runs on back roads and trails, some with the same guides that do the jamborees...they always tell us to shift into 4 wd 'high' as soon as we get on the trails, and once we get into 'rough stuff', they tell us to go into 4 wd 'low'. Generally...(I drive an automatic) we run a lot of 4 wd low simple because you don't have to ride the brakes all the time! Especially on long downhills, when everyone in front of you is just crawling, dropping to low and 1st gear means you aren't replacing your brakes every year. And no one I know yet has done any damage to anything (axles, bearings, drivetrain) by driving this way...
Roland

aelwero

09-10-2010 11:53 AM

Quote:

Originally Posted by Baileys Daddy
(Post 765940)

I have to agree with Thaduke. I have always driven in 2wd until 4hi was needed and then when all else fails switch to 4lo.....But this is just me and I only have experience in deep ocean sand and snow......
BD

I read that as "deep ocean, sand, and snow" the first time :rofl:
do the mods still get upset if we mention chadwick?

Automatic, and usually don't shift until I'm already stuck. Jimbo's gonna jump in and tell you NOT to do that, and his concern is valid. If you are spinning the tires in mud and shift into 4Hi you can do some serious damage, and if you shift completely stopped it can be hard to "line up" the t-case in an auto.

shifting "on the fly" before the fact is the safest way, but I'm eccentric, so...

JIMBOX

09-10-2010 11:59 AM

:D Heh Heh--BINGO-!!

Quote:

Originally Posted by aelwero
(Post 766154)

I read that as "deep ocean, sand, and snow" the first time :rofl:
do the mods still get upset if we mention chadwick?

Automatic, and usually don't shift until I'm already stuck. Jimbo's gonna jump in and tell you NOT to do that, and his concern is valid. If you are spinning the tires in mud and shift into 4Hi you can do some serious damage, and if you shift completely stopped it can be hard to "line up" the t-case in an auto.

shifting "on the fly" before the fact is the safest way, but I'm eccentric, so...

Good day aelwero--:punk:

:rofl::rofl: JIMBO

jeffk42

09-10-2010 12:01 PM

Quote:

Originally Posted by Croakus
(Post 766114)

If you can get to that article, I think it's a great overview.

The problem is, a lot of what you're going to get is opinion. Including this ;-) ... but in my 20 some years of experience, 4wd is fine on almost everything except pavement. Even then, it's reasonable to engage on slippery roads like snow and ice.

Personally, you won't find me driving on gravel without 4wd ... but that's a long story for another thread ;)

As far as damage goes ... I've never heard anyone say they did damage by driving in 4wd when they shouldn't have. If anyone here has a story I'd be really interested in hearing it. The only problem I've actually seen is binding / tires slipping when the gears got out of synch ... and while that can't be good, I've never actually seen anything break. If I were to guess, I'd say you'd probably blow a $50 U-Joint before anything else.

Jeeps are tough vehicles and have one of the most time proven 4wd designs on the planet. IMO you'd have a hard time breaking it just by using it now and then. Just be reasonable with it and you should be OK.

I like this response. It's always good to exercise the proper care, but you'll find a lot of people implying that if you the slightest thing wrong (like 4WD on a tightly-packed dirt road) you'll immediately see pieces of your Jeep bouncing down the road through your rearview mirror just before all of the wheels lock up, sending you into a ravine where your vehicle promptly bursts into flames.

Okay, maybe I'm embellishing a little, but the point is that it's easy to get unnecessarily frightened by the scary consequences. I should know, all this talk on the various sites made me nervous and I'm still a couple of weeks out from getting my Wrangler. But this is the post that resonated with me the most -- heed the warnings, exercise proper care, but don't be afraid of the lever, either. :-)

daggo66

09-10-2010 12:29 PM

I use 4Lo when I'm on a trial that requires low speed crawling. This saves the clutch tremendously. The JK has a no stall feature that lets you brake in first gear and 4Lo. In beach sand I use 4 Hi with ESP turned off.

ESP

09-10-2010 01:01 PM

What is everyone talking about? I've been driving everywhere in 4lo since I bought my Jeep. It used to make this really funny noise when I got on the interstate but after a few very loud pops everything was fine! The engine just need some "break"-ing in.:rofl:

dfwislander

09-10-2010 03:01 PM

Wow, thanks everyone. Even through all the opinions, I think I have a better idea and will feel more comfortable than I did before. Now that's the spirit of a jeep community! I should have mentioned that mine is an auto. I do have one thing I'm not clear on, it was my understanding that shifting to low should be done when the vehicle is stopped and trans in neutral. Thoughts?

silvrevo

09-10-2010 03:11 PM

Oooooooooo Crap............

I thought 4 Low / 4 High was based on your Elevation.

Croakus

09-10-2010 03:19 PM

Quote:

Originally Posted by dfwislander
(Post 766332)

Wow, thanks everyone. Even through all the opinions, I think I have a better idea and will feel more comfortable than I did before. Now that's the spirit of a jeep community! I should have mentioned that mine is an auto. I do have one thing I'm not clear on, it was my understanding that shifting to low should be done when the vehicle is stopped and trans in neutral. Thoughts?

It's in the owner's manual ;) ... but seriously though ... shift auto to neutral and while rolling VERY slowly (under 5 miles an hour) shift into 4 low. Basically you're moving some very big gears together inside that T-Case and the slow movement will help them mesh with minimal effort.

If you try to do it while stopped the teeth probably won't mesh ... could mess up the shifter.

JIMBOX

09-10-2010 03:22 PM

:) NO never try to shift the JK when you're stopped dead--you should think ahead of any problems and already be in 4hi/4lo

Quote:

Originally Posted by dfwislander
(Post 766332)

Wow, thanks everyone. Even through all the opinions, I think I have a better idea and will feel more comfortable than I did before. Now that's the spirit of a jeep community! I should have mentioned that mine is an auto. I do have one thing I'm not clear on, it was my understanding that shifting to low should be done when the vehicle is stopped and trans in neutral. Thoughts?

Since you have an auto-you can stay in 4hi for most of your travels, but

If you're towing/climbing hills/sand/beach--you should be in 4lo, this will help keep the auto from overheating, it takes the load off the tranny bands, (heat generators) and the torque converter-

:rofl::rofl: JIMBO

daggo66

09-10-2010 03:23 PM

Quote:

Originally Posted by silvrevo
(Post 766339)

Oooooooooo Crap............

I thought 4 Low / 4 High was based on your Elevation.

Don't worry, you'll never need to use it anyway.

daggo66

09-10-2010 03:25 PM

Quote:

Originally Posted by Croakus
(Post 766350)

It's in the owner's manual ;) ... but seriously though ... shift auto to neutral and while rolling VERY slowly (under 5 miles an hour) shift into 4 low. Basically you're moving some very big gears together inside that T-Case and the slow movement will help them mesh with minimal effort.

If you try to do it while stopped the teeth probably won't mesh ... could mess up the shifter.

It's simply amazing the stuff you can find in that little book. You can also download a .pdf copy from Jeep.com.

jk'n

09-10-2010 03:29 PM

Quote:

Originally Posted by dfwislander
(Post 766332)

Wow, thanks everyone. Even through all the opinions, I think I have a better idea and will feel more comfortable than I did before. Now that's the spirit of a jeep community! I should have mentioned that mine is an auto. I do have one thing I'm not clear on, it was my understanding that shifting to low should be done when the vehicle is stopped and trans in neutral. Thoughts?

That one is in the manual. You can go 2 to 4H I think up to 50MPH although I usually shift under that speed. 4H to 4L you should be just crawling or stopped. If you shift 4H to 4L in an automatic and the shifter is in drive, when you go into neutral on the transfer case, the engine gears will be moving and the gears on the output side of the transfer case will not, so you should be in neutral on the tranny when shifting 4H to 4L.

jk'n

09-10-2010 03:30 PM

Dang, quite a few posts happened suggesting the manual while I was typing ;)